1. Field of the Invention
The present invention relates to the field of liquid crystal displaying, and in particular to a dark spot repair method of a liquid crystal panel and a liquid crystal panel.
2. The Related Arts
Liquid crystal displays have a variety of advantages, such as thin device body, low power consumption, and being free of radiation, and are thus widely used. Most of the liquid crystal displays that are currently available in the market are backlighting liquid crystal displays, which comprise a liquid crystal panel and a backlight module. The operation principle of the liquid crystal panel is that liquid crystal molecules are interposed between two parallel glass substrates and a driving voltage is applied to the two glass substrates to control rotation direction of the liquid crystal molecules in order to refract out light emitting from the backlight module for generating images. Since the liquid crystal panel itself does not emit light, light must be provided from the backlight module in order to normally display images. Thus, the backlight module is one of the key components of a liquid crystal display. The backlight modules can be classified in two types, namely a side-edge backlight module and a direct backlight module, according to the position where light gets incident. The direct backlight module comprises a light source, such as a cold cathode fluorescent lamp (CCFL) or a light-emitting diode (LED), which is arranged at the backside of the liquid crystal panel to form a planar light source directly supplied to the liquid crystal panel. The side-edge backlight module comprises an LED light bar, serving as a backlight source, which is arranged at an edge of a backplane to be located rearward of one side of the liquid crystal panel. The LED light bar emits light that enters a light guide plate (LGP) through a light incident face at one side of the light guide plate and is projected out of a light emergence face of the light guide plate, after being reflected and diffused, to pass through an optic film assembly to form a planar light source for the liquid crystal panel.
To enhance the quality of displaying in large view angles, in other words, to make colors displayed at an inclined view angle and a front view angle well consistent with each other, a liquid crystal panel is often comprised of a structure of pixel that adopts a so-called charge-share pixel structure. As shown in FIG. 1, the charge-share pixel structure generally divides a main pixel into two portions, namely a first sub-pixel 100 and a second sub-pixel 200, wherein the first sub-pixel 100 comprises a first thin-film transistor T100 connected to a first gate line and second sub-pixel 200 comprises a second thin-film transistor T200 connected to the first gate line and a third thin-film transistor T300 connected to the second thin-film transistor T200 and a second gate line. When the first thin-film transistor T100 and the second thin-film transistor T200 are simultaneously activated by a control signal applied to the first gate line, a liquid crystal capacitor Clc100 of the first sub-pixel 100 and a liquid crystal capacitor Clc200 of the second sub-pixel 200 show the same grey level voltage. Subsequently, when the third thin-film transistor T300 is activated by a control signal applied to the second gate line, since the liquid crystal capacitor Clc100 shares charges with voltage-division capacitors Ccs100, Ccs200, the liquid crystal capacitor Clc100 of the first sub-pixel 100 would have a different grey level voltage from the liquid crystal capacitor Clc200 of the second sub-pixel 200 so as to improve color shifting phenomenon in inclined view angles and thus greatly enhance the quality of displaying at large view angles.
For the currently available technique level, it is inevitable that one or more defect main pixels exist in a liquid crystal panel. To improve the yield rate of liquid crystal panels, it is necessary to carry out dark sport repair for those defect main pixels. A conventional dark spot repair method is to cut off the wire of the source terminal and the wire of the drain terminal of the first thin-film transistor T100 and also the wire of the drain terminal of the second thin-film transistor T200 (as indicated by X marks in FIG. 1) and at the same time, the transparent conductive film (Indium tin oxide, ITO) and the common electrode (Com line) of the main pixel are soldered together and shorted (as indicated by bold line in FIG. 10 so as to repair and make the defect main pixel in a normally-dark state to increase the yield rate of the liquid crystal panel. Carrying out dark spot repair on a defective main pixel with this method takes a long time and requires numerous repairing tools thereby leading to reduction of throughput and increase of manufacture cost.